The present invention relates to a water heating system which employs a preheater. Preheaters for hot water heating systems are not per se new. It has been suggested many times in the past that hot flue gases may be used in order to preheat incoming water for a hot water tank. This invention relates to an improvement upon this basic system.
The improvement of this invention provides for preheating of all incoming cold water and for simultaneously recirculating portions of water stored within the storage tank in order to increase the average temperature of the stored water. The result is an increased fuel efficiency over the prior art preheater systems.
Accordingly, one object of this invention is to provide a water heating system which utilizes hot flue gases to preheat not only incoming cold water, but also for recirculating and preheating water from the storage tank of the system. Another object of this invention is to provide a water heating system which is of increased fuel efficiency.
Yet another object of this invention is to provide a system which will by natural convections, continually recirculate water from the water storage tank through the preheater during periods of time when water is not being drawn off from the hot water heater.
Another object of this invention is to provide an improved preheating device which emloys baffles to provide air turbulence and increased heat exchange efficiency between hot flue gases and water circulating through the hot flue gases inside of a copper tubing.
Other objects and advantages of this invention will become readily apparent from the following description of the invention.